Engineering Supramolecular Binding Sites in a Chemically Stable Metal‐Organic Framework for Simultaneous High C<sub>2</sub>H<sub>2</sub>Storage and Separation
Kai Shao, Hui‐Min Wen, Congcong Liang, Xiaoyan Xiao, Xiao‐Wen Gu, Banglin Chen, Guodong Qian, Bin Li
Abstract
Abstract Developing porous materials to overcome the trade‐off between adsorption capacity and selectivity for C 2 H 2 /CO 2 separation remains a challenge. Herein, we report a stable HKUST‐1‐like MOF (ZJU‐50a), featuring large cages decorated with high density of supramolecular binding sites to achieve both high C 2 H 2 storage and selectivity. ZJU‐50a exhibits one of the highest C 2 H 2 storage capacity (192 cm 3 g −1 ) and concurrently high C 2 H 2 /CO 2 selectivity (12) at 298 K and 1 bar. Single‐crystal X‐ray diffraction studies on gas‐loaded ZJU‐50a crystal unveil that the incorporated supramolecular binding sites can selectively take up C 2 H 2 molecule but not CO 2 to result in both high C 2 H 2 storage and selectivity. Breakthrough experiments validated its separation performance for C 2 H 2 /CO 2 mixtures, providing a high C 2 H 2 recovery capacity of 84.2 L kg −1 with 99.5 % purity. This study suggests a novel strategy of engineering supramolecular binding sites into MOFs to overcome the trade‐off for this separation.